effect-io-ai

Package: effect
Module: Option

Option.filterMap

Transforms and filters an Option using a Filter callback.

When to use

Use to transform an Option’s present value and discard it when the Filter fails.

Details

The callback returns a Result: Result.succeed keeps and transforms the value, while Result.fail discards it.

Example (Filtering and transforming)

import { Option, Result } from "effect"

console.log(Option.filterMap(
  Option.some(2),
  (n) => (n % 2 === 0 ? Result.succeed(`Even: ${n}`) : Result.failVoid)
))
// Output: { _id: 'Option', _tag: 'Some', value: 'Even: 2' }

See

• filter for predicate-based filtering

Signature

declare const filterMap: { <A, B, X>(f: Filter.Filter<A, B, X>): (self: Option<A>) => Option<B>; <A, B, X>(self: Option<A>, f: Filter.Filter<A, B, X>): Option<B>; }

Source

Since v2.0.0